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Determination of soil infiltration rate equation based on soil properties using multiple linear regression

Harisuseno Donny, Cahya Evi N.

Journal of Water and Land Development

2020

no. 47

77--88

Infiltration process plays important role in water balance concept particularly in runoff analysis, groundwater recharged, and water conservation. Hence, increasing knowledge concerning infiltration process becomes essential for water manager to gain an effective solution to water resources problems. This study employed multiple linear regression for estimating infiltration rate where the soil properties used as the predictor variable and measured infiltration rate as the response variable. Field measurement was conducted at sixteen points to obtain infiltration rate using double ring infiltrometer and soil properties namely soil porosity, silt, clay, sand content, degree of saturation, and water content. The result showed that measured infiltration rate had an average initial infiltration rate (f0) of 6.92 mm∙min–1 and final infiltration rate (fc) of 1.49 mm∙min–1. Soil porosity and sand content showed a positive correlation with infiltration rate by 0.842, 0.639, respectively, while silt, clay, water content, and degree of saturation exhibited a negative correlation by –0.631, –0.743, –0.66 and –0.49, respectively. Three types of regression equations were established based on type of soil properties used as predictor variables. The model performance analysis was conducted for each equation and the result shows that the equation with five predictor variables fMLR_3 = – 62.014 + 1.142 soil porosity – 0.205 clay, – 0.063 sand – 0.301, silt + 0.07 soil water content with R2 (0.87) and Nash–Sutcliffe (0.998) gave the best result for estimating infiltration rate. The study found that soil porosity contributes mostly to the regression equation that indicates great influence in controlling soil infiltration behavior.

Modelowa ocena wpływu parametrów otoczenia na napełnienie i parametry pracy silnika

Lisowski M., Kowalek S.

Autobusy : technika, eksploatacja, systemy transportowe

2013

R. 14, nr 10

176-179

W artykule przedstawiono wyniki analiz wpływu parametrów otoczenia (temperatury i ciśnienia) na napełnienie cylindrów silnika spalinowego. Analizę prowadzono na podstawie wyników badań modelowych wykonanych dla silnika o zapłonie samoczynnym. Wykorzystując model matematyczny, oparty na równaniach N-S, wyznaczono wartości masy powietrza pozostającego w cylindrze po zamknięciu zaworu dolotowego dla różnych wartości ciśnień i temperatury. Badania symulacyjne wykonywane były dla różnych prędkości obrotowych wału korbowego silnika. Wyniki przedstawiono w formie charakterystyk współczynnika napełnienia w funkcji temperatury otoczenia i ciśnienia barometrycznego przy ustalonej wartości prędkości obrotowej. Dla obu parametrów wyznaczono równanie linii trendu stanowiące jednocześnie wzór do obliczania współczynnika korekcji dla napełnienia.

This paper presents the results of analyzes of the impact environmental parameters (temperature and pressure) to ﬁll the cylinder internal combustion engine. The analysis was performed based on the results of model tests carried out on a diesel engine. Using a mathematical model based on equations, N-S, the values of the air mass remaining in the cylinder after intake valve closure for different values of pressure and temperature. Simulation studies were carried out for different speeds of the engine. The results are shown in the form of characteristics as a function of the ﬁlling ratio of ambient temperature and barometric pressure at the set speed value. For both parameters were determined trend line equation which also serves as a model for calculating the correction factor for the ﬁlling.